Drug smuggling tunnels discovered between US and Mexico

The unfinished tunnel discovered by authorities in Tijuana designed to smuggle drugs into the United States.

An Immigration and Customs Enforcement spokeswoman said Thursday that an approximately 220-yard passage, pictured at right, was lit and ventilated. It began under a bathroom sink inside a warehouse in Tijuana and did not cross the border into San Diego.

Elsewhere, a 240-yard completed passage was discovered less than a week ago near Yuma, Ariz. U.S. authorities say that tunnel was operational.

As U.S. authorities heighten enforcement on land, tunnels have become an increasingly common way to smuggle enormous loads of marijuana into the country. More than 70 passages have been found on the border since October 2008, surpassing the number of discoveries in the previous six years.

This image provided by the US Drug Enforcement Administration(DEA) on Thursday shows the US Entrance to a cross border tunnel linking a commercial building in San Luis, Arizona to Mexico that was discovered through a probe conducted by the DEA. The DEA on Thursday announced the details of a 240-yard (219m)passageway that was equipped with lighting and ventilation. US Justice Department officials say the sophisticated tunnel was used to transport drugs from Mexico to the commercial building on the Arizona side. Authorities said the investigation also included arrests and drug seizures.

DEA via AFP - Getty Images

The US Entrance to a cross border tunnel linking a commercial building in San Luis, Arizona to Mexico.

DEA via AFP - Getty Images

The cross border tunnel linking a commercial building in San Luis, Arizona to Mexico.

DEA via AFP - Getty Images

DEA image of 39 pounds(14.5kg) of methamphetamines recovered by officials from a cross border tunnel linking a commercial building in San Luis, Arizona to Mexico.